That is exactly what I did a year ago.

On the advice of several of the folks here, I got a receiver with pre-outs for every channel (Yamaha RXV650). From the start, I continued to use my old Carver amp. It drove the Vandersteens (inefficient) well as it handled high current loads. The Yamaha couldn't get any sound out of them. Now I am using a pair of DIY monitors, but still use the Carver. It cranks.

My latest thing is a "musical" subwoofer. Two of them, actually. I am glad I have all the pre-outs. I wanted to be able to hook up stereo subs to support the monitors and have them integrate seamlessly, the monitors fall off at mid-bass. I will be running the pre-outs for "Main L and R" to each subwoofer. My subs allow for a pass through, which I run back to the Carver. Thus, the receiver controls all the preamps, and the power amps for center and rears. The Carver powers the mains. The dual subs are each self powered. They pick up the full L or R signal, filtering at 85 Hz. Thus they are stereo. I am glad I had such flexibility. One sub is up and running, the effect is fantactic. The other is work in progress.

jocko